Golang reverse formatting with regex

main.go

package main

import (
  "fmt"
  "reflect"
  "regexp"
  "sort"
)

func main() {
  // Test data
  data := map[string]string{
    "foo.yaml": `apiVersion: v1
metadata:
  name: foo
`,
    "bar.yaml": `kind: Pod
metadata:
  name: bar
`,
  }

  // Extract keys
  keys := []string{}
  for k, _ := range data {
    keys = append(keys, k)
  }
  sort.Strings(keys)

  // Prepare output
  output := ""

  // Build the output
  for _, k := range keys {
    output += fmt.Sprintf("---\n# Source: %s\n%s\n", k, data[k])
  }

  r := regexp.MustCompile("(?sm)^---\n^# Source: (?P<path>.*?)$\n(?P<content>.*?^$)\n")

  matches := r.FindAllStringSubmatch(output, -1)

  recoveredData := map[string]string{}

  for _, match := range matches {
    recoveredData[match[1]] = match[2]
  }

  fmt.Println(reflect.DeepEqual(data, recoveredData))
}